Actualitas

Actualitas is a Latin philosophical term meaning actuality, the state of being actual as opposed to potential. It figures prominently in Aristotelian and medieval thought, where it is paired with potentia to explain how things come to be and how they change. In this framework, actuality designates the realized form, act, or existence that a thing has when its potential is actualized by a determining cause or form. The distinction between actus and potentia is foundational in hylomorphic theory, which holds that matter provides potential while form provides actuality.

In scholastic usage, actualitas covers both the actualized properties of a substance and the actual operations or events that occur in time. It can describe the difference between what something can become and what it already is, as well as the present state of affairs in contrast to possible futures. In theology and metaphysics, the term is used to analyze the nature of being, change, and causation.

Today, actualitas is primarily encountered in historical-philosophical contexts, Latin glossaries, and translations of classical texts. It remains a key term for understanding the distinction between what exists in reality versus what exists only in potential, and it helps frame discussions of modality and the dynamics of becoming.